A powdered soft drink preparation normally contain a carbohydrate and a sour agent as a main component, and is prepared by additionally adding a subraw material such as fruit juice. It is necessary that the powdered soft drink preparation maintains the dried state as much as possible because of its high moisture absorption. That is, the soft drink preparation causes deterioration such as coagulation, browning, discoloration in the presence of water, which results in deterioration of the quality.
In addition, this preparation always contain about 1% of water derived from the raw material even if water is severely controlled. When the component causing the reaction between water and the above main component is present in the subraw material, for example, when a basic nutritive component is present, the neutralization reaction proceeds with time. When amino acid is added, the browning due to Mailard reaction arises. Therefore, there is a drawback in both cases that it becomes very difficult to maintain the preparation stably.
Furthermore, even if the preparation is reserved in an enclosed container, it is difficult to avoid deterioration of quality and change of taste with time, which are caused by the above-described water of about 1%, water adhered on raw materials, water to be formed by the neutralization reaction between the added components. Therefore, it is essential for the preparation to use a desiccant at present. Thus, it is requested to develop a novel method for preventing deterioration due to water for a long period of time to maintain the quality.